Store data from columns of a text file to an array. in C

Question

I have a text file that looks like this:

Process Priority    Burst   Arrival
1   8   15  0
2   3   20  0
3   4   20  20
4   4   20  25
5   5   5   45
6   5   15  55
7   9   10  70
8   6   15  100
9   5   15  105
10  5   15  115

The columns are separated by tabs. I need to ignore the first line and then all entries from one column store them into an array such as "int process[10]".

I have found this thread :Reading in a specific column of data from a text file in C , however the way is done is very specific to the way the data is set up in the op's question.

thanks.

Answer 1

Give this a try. This grabs all columns you have from the file and is compliant with ansi:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void parseLine(char *line, int *num1, int *num2, int *num3, int *num4 ){

    char* temp;

    temp = strchr(line,'\t');
    temp[0] = '\0';
    *num1 = atoi(line);
    line = temp + 1;

    temp = strchr(line, '\t');
    temp[0] = '\0';
    *num2 = atoi(line);
    line = temp + 1;

    temp = strchr(line, '\t');
    temp[0] = '\0';
    *num3 = atoi(line);
    line = temp + 1;

    *num4 = atoi(line);
}

int main(void)
{
    FILE* fp;
    char line[100];
    
    int process[10];
    int priority[10];
    int burst[10];
    int arrival[10];
    int i;
    int j;

    i = 0;

    if ((fp = fopen("./yourfile.txt", "r")) == NULL)
    {
        printf("Error Opening File\n");
        exit(1);
    }

    fgets(line, sizeof(line), fp);


    while (fgets(line, sizeof(line), fp))
    {
        parseLine(line, &process[i],&priority[i],&burst[i],&arrival[i]);
        i++;
    }

    for (j = 0; j < 10; j++){
        printf("Process: %d, Priority: %d, Burst: %d, Arrival: %d\n", process[j], priority[j], burst[j], arrival[j]);
    }

    fclose(fp);
    return 0;
}